Hair not only protects the surface of the skin but serves an esthetic purpose. Hair grows from hair follicles found all over the skin. The hair follicle, a gland-equipped sac-like structure, takes root in the dermis and extends upward to reach the epidermis; hence, the hair follicle consists of a dermal portion and an epidermal portion. The dermal portion of the hair follicle comprises dermal papillae (DP) and a dermal sheath (DS). The epidermal portion of the hair follicle comprises an inner root sheath (IRS) and an outer root sheath (ORS). The human scalp is the skin that covers the top of the human head and, of course, comprises the dermis and the epidermis.
Hair growth is a continuous lifelong process that takes place in cycles of four phases: anagen (growth), catagen (regression), telogen (rest), and exogen (shedding). A prolongation of the telogen phase, coupled with the ensuing failure to enter a new anagen phase, is a proven pathological cause of alopecia (hair loss) of an extent from hair thinning to baldness. Alopecia brings about psychological problems in both men and women. The symptoms can include loss of self-esteem, anxiety, fear and negative body image.
To mitigate alopecia, the prior art effectuates hair restoration by follicular unit transplantation (FUT) which involves: removing from the occipital portion of the human scalp a long, thin donor strip; performing stereo-microscopic dissection on the strip to remove individual follicular units therefrom; and implanting the individual follicular units in the recipient area of the human scalp. However, FUT has its own drawbacks. For example, FUT leaves a linear donor scar in the donor area of the human scalp. The drawback is overcome by a subsequent hair restoration technique known as follicular unit extraction (FUE). FUE does not leave any visible scar in the donor area of the human scalp, as FUE uses a biopsy punch to remove individual follicular unit grafts from the occipital portion and temporal portions of the human scalp. The advantage that the FUE method has over FUT is that FUE does not leave a linear donor scar, causes less bleeding, and causes less post-operative discomfort. However, FUE has its own drawbacks. For example, FUE is time-consuming, expensive, and is not suitable for patients who require transplantation of a large number of hair follicular units. Furthermore, not only does the success of FUE largely depend on the experience of the hair transplant team, but FUE is notorious for a likelihood of an increased risk of follicular damage in extraction which can lead to sub-optimal growth of the hair transplant.
Accordingly, it is imperative to develop a hair restoration technique that overcomes the aforesaid drawbacks of the prior art.